now that we have some information to go on.....
this truck should have the GE SX controller
code -86 is for accelerator pot values out of range during self test during auto-calibration routine. (during startup it failed the check)

check your accelerator
it either has defective pot or bad wiring associated with that circuit.

A handset or the proper laptop software will be needed to verify and clear codes and check operations

and since i get the impression you did not know what i meant about the 'type of controls' this unit has i suggest you take edwardt's and my advise and call a qualified tech to come out and verify diagnosis and make the needed repairs.

this code means that someone with training in how to safely work on electric motive forklift controls needs to be who does the rest of the troubleshooting and repair in order to be sure no one gets hurt either durring the repair of or from the adjustments made.
It is time for a service call to your local electric forklift repair technician.

It"s model is E C15K

Serial # A3EC110241

controls meaning? Is is Electric with forward and reverse lever on left of stering colomn. has 3 diff contols for forks. Hope that helps. Thanks so much Jeff

more info would help some
model?
serial?
type of controls?